免疫第四章.ppt

单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,“,”,单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,“,”,单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,编辑母版文本样式,第二级,第三级,第四级,第五级,*,T cell recognition of a peptide-MHC complex,1.,组织相容性：指在不同个体之间进行组织细胞移植时，受体和供体,之间相互接受的程度。,2.,组织相容性抗原：引起排斥反应的抗原，也成为移植抗原。,3.,主要组织相容性抗原：机体参与排斥反应的抗原系统很多，其中能,引起强而迅速排斥反应的抗原。,4.MHC,：,主要组织相容性复合体，编码主要组织相容性抗原系统的紧,密连锁的基因群。,Discovery of the mouse MHC,Structure of MHC molecules,Downloaded from:StudentConsult(on 21 September 2008 08:12 AM),2005 Elsevier,Class I MHC molecules,Downloaded from:StudentConsult(on 21 September 2008 08:12 AM),2005 Elsevier,Class II MHC molecules,MHC molecules,MHC class I,MHC class II,chain,2,microglobulin,：,invariant but essential,chain,chain,1,2,3,：,binds CD8 molecule on,T cells,2,1,1,2,：,binds CD8 molecule on,T cells,Peptide binding site,Peptide binding site,Properties of MHC genes,MHC haplotype,Linkage disequilibrium,MHC codominance,polymorphism,Polymorphic residues of a class I MHC molecule,Properties of MHC molecules,Each MHC molecules consists of an extracellular peptide-binding cleft,or groove,followed by immunoglobulin(Ig)-like domains and is anchored to the cell by transmembrane and cytoplasmic domains.,The polymorphic amino acid residues of MHC molecules are located in and adjacent to the peptide-binding cleft.,The nonpolymorphic Ig-like domains of MHC molecules contain binding sites of the T cell molecules CD4 and CD8.(T cell coreceptors),Table 5-1.Features of Class I and Class II MHC Molecules,peptides binding to MHC molecules,Binding of peptides to MHC molecules,Characteristics,of peptide-MHC interactions,Structural basis,of peptide binding to MHC molecules,Characteristics of peptide-MHC interactions,Characteristics of peptide-MHC interactions,MHC-binding residues and T cell receptor contact residues of a model peptide antigen,Genomic organization of the MHC,Genomic organization of the MHC,Expression of MHC molecules,Class I molecules are constitutively expressed on virtually all nucleated cells,whereas class II molecules are normally expressed on only dendritic cells,B lymphocytes,macrophages,and a few other cell types.,The expression of MHC molecules is increased by cytokines produced during both innate and adaptive immune responses.,The rate of transcription is the major determinant of the level of MHC molecule synthesis and expression on the cell surface.,Expression of MHC molecules,